Flower-like NiCo2O4 nanoflake surface covered on carbon nanolayer for high-performance electro-oxidation of non-enzymatic glucose biosensor

Abstract

The high porous nickel cobalt oxide flower-like nanoflake (NF) structured materials with (C/NiCo2O4-1 and C/NiCo2O4-2) and without (NiCo2O4) the presence of dopamine as a carbon source were synthesized by a simple hydrothermal method for non-enzymatic glucose sensing. The structural and morphological characteristics of as-synthesized materials were confirmed using transmission electron microscopy, field emission scanning electron microscopy, X-ray photoelectron spectroscopy, and X-ray diffraction analysis. The transmission electron microscopy analysis of C/NiCo2O4-1 NF materials reveals that a flower-like structure of NiCo2O4 NF covered over the surface of carbon in the hybrid composite. The electrochemical properties of as-synthesized material were determined from cyclic voltammetry and chronoamperometry analysis. Among the NiCo2O4 NF, C/NiCo2O4-1 NF, and C/NiCo2O4-2 NF structured materials, the C/NiCo2O4-1 NF exhibits a remarkable electrochemical performance toward glucose oxidation with a high linear range (0.0001–15.28 mM), high-sensitivity (779.35 μA mM−1 cm−2), and ultra-low detection (86 μM). Moreover, the C/NiCo2O4-1 NF electrode indicates excellent recoveries of glucose in human blood serum samples. The obtained results illustrate that the good features of C/NiCo2O4-1 NF electrode materials have the potential to be used as a non-enzymatic glucose sensor.